[Python-ideas] Dunder method to make object str-like

[Nikolaus Rath]

On Apr 11 2016, Ethan Furman <ethan-gcWI5d7PMXnvaiG9KC9N7Q at public.gmane.org> wrote:
> On 04/11/2016 07:43 AM, Nikolaus Rath wrote:
>> On Apr 10 2016, Ethan Furman wrote:
>
>>> By having a well-defined protocol and helper function we not only make
>>> our own lives easier but we also make the lives of third-party
>>> libraries and experimenters easier.
>>
>> To me this sounds like catering to a hypothetical audience that may want
>> to do hypothetical things. If you start with the above, and people
>> complain that their favorite non-pathlib path library is not supported
>> by the stdlib, you can still add a protocol. But if you add a protocol
>> right away, you're stuck with the complexity for a very long time even
>> if almost no one actually uses it.
>
> The part of "make our own lives easier" is not a hypothetical
> audience.

My assumption was that "own" refers to core developers here, while..

> Making my own library (antipathy) work seamlessly with pathlib and
> DirEntry is not hypothetical.

..here you seem to be wearing your third-party maintainer hat :-).


As far as I can see, implementing a protocol instead of adding a few
isinstance checks is more likely to make the life of a CPython developer
harder than easier.


Best,
-Nikolaus

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